See also:

How to calculate percent change - Step by Step

Percent increase or decrease measures percent changes between two values. Use this calculator when comparing an old value to a new value.

The Percent Change Calculator uses this formula:

% change =

(

New Value - Old Value

)

× 100%

|Old Value|

Where |Old Value| represents the absolute value of the reference (this is made in order to work well with both positive and negative values of Old Value and New Value. Note that percent change and relative change mean the same thing. It can be a percent increase or a percent decrease depending on the new and the old values. If the new value is greater than the old value, the result will be positive and we will have a increase. On the other hand, if the new value is smaller than old value, the result will be negative and we will have a we have a decrease. The old value, as a reference, may be: a theoretical, the actual, the correct, an accepted, an optimal, the starting, and so on. See more about percent percent change here.

Here are the solutions to the questions stated above:

1) What is the percentage decrease from 400 to 170?

Use the above formula to find the percent change. So, replacing the given values, we have

Percent change = [(170 - 400) / 400] x 100 =
-57.5 % (decrease)

Where: 400 is the old value and 170 is the new value. In this case we have a % of decrease because the new value is smaller than the old value.

2) What is the absolute Decrease from 400 to 170?

This problem is not about percent or relative change, but about absolute change. Its solution is very simple:

Absolute change, or

change = new value - old value

= 170 - 400 = -230 (decrease)

Percent Change Calculator

Please link to this page! Just right click on the above image, choose copy link address, then past it in your HTML.